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Total syntheses of spiroviolene and spirograterpene A: a structural reassignment with biosynthetic implications.

ABSTRACT: The recent natural product isolates spiroviolene and spirograterpene A are two relatively non-functionalized linear triquinane terpenes with a large number of structural homologies. Nevertheless, three significant areas of structural disparity exist based on their original assignments, one of which implies a key stereochemical divergence early in their respective biosyntheses. Herein, using two known bicyclic ketone intermediates, a core Pd-catalyzed Heck cyclization sequence, and several chemoselective transformations, we describe concise total syntheses of both natural product targets and propose that the structure of spiroviolene should be reassigned. As a result, these natural products possess greater homology than previously anticipated.

SUBMITTER: Chi HM

PROVIDER: S-EPMC8162393 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Total syntheses of spiroviolene and spirograterpene A: a structural reassignment with biosynthetic implications.

Chi Hyung Min HM Cole Charles J F CJF Hu Pengfei P Taylor Cooper A CA Snyder Scott A SA

Chemical science 20200930 40

The recent natural product isolates spiroviolene and spirograterpene A are two relatively non-functionalized linear triquinane terpenes with a large number of structural homologies. Nevertheless, three significant areas of structural disparity exist based on their original assignments, one of which implies a key stereochemical divergence early in their respective biosyntheses. Herein, using two known bicyclic ketone intermediates, a core Pd-catalyzed Heck cyclization sequence, and several chemos ...[more]

PMID: 34094343

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